Grease dispensing apparatus



Patented Feb. 28, 1939 UNITED STATES PATENT OFFICE 2 Claims.

My invention relates to a grease dispensing apparatus and more .particularly to an apparatus for dispensing heavy greases.

In order toY dispense heavy greases, consider- 5 able pressure is required. In the grease dispensers of the prior art, this pressure has been obtained in most instances by means of an air piston operating a plunger of much smaller cross sectional y area in order to obtain a mechanical advantage. 1G Of necessity the grease dispensing device must be of limited size and it is diicult to obtain a high rate of flow, due to the fact that the grease dispensing plunger must complete a plurality of strokes to move an appreciable quantity of grease.

The average rate of ilow of an eiiicient grease dispensing device using an air piston is about seven ounces of grease per minute.

TheV use of air has in practice shown several disadvantages. Air leaking by the piston causes oxidation, polymerization and sludging of the grease. The oxidation forms organic acids and corrosive compounds,y which cause corrosion. Air llocks are formed with the result that the grease is channeled by the air and frequently filled with small bubbles of air.

Air always contains an amount of moisture which causes the grease to break down due to the hydrolyzation of the soaps employed in forming the grease.

One object of my invention is to provide a hydraulic grease dispensing device in which no air is employed to move the grease.

Another object of my invention is to provide a grease dispensing apparatus which is capable of dispensing a heavy grease at a high rate.

, A further object of my invention is to provide a grease dispensing apparatus which is simple of, construction Aand flexible in operation.

. Other and further objects of my invention will 40 appear from the following description.

Y The accompanying drawing is a diagrammatic view showing a cross section of an apparatus embodying one form of my invention.

A receptacle I is provided with a readily removable cover 2 secured thereto by means of nuts 3, which are threaded upon studs 4. The cover 2 carries aithreaded shaft 5 adapted to be rotated by a crank 6. The threaded shaft 5 engages a piston 1 which is threaded centrally and is adapted to be moved upon rotation of the shaft 5. Y The piston 1 carries a packing 8 of leather or other suitable material, adapted to prevent the grease from squeezing by the piston 5j 1. The bottom of container I is connected by means of a pipe 9 to the dispensing cylinder I0 through the medium of a check valve II. A piston I2 p-rovided with upper packing leather I3 and lower packing leather I4 is disposed within the cylinder IB. Communicating with the lower 5 portion of cylinder I Il is a manifold I5 having branched outlet pipes I6, I1 and I 3 to which the grease dispensing hose I9, 20, and 2| are connected by means of suitable unions 22, 23, and 24. Each hose is provided with a grease dis- '10 pensing nozzle 25. It is to be understood that any suitable number of grease dispensing connections may be employed.

The upper end of cylinder IIB is provided with a valve housing 25 in which valve 2 is adapted 15 to seat. A container 28, which has at least the same capacity as cylinder I3, is connected with cylinder IQ through the valve connection 26, by means of a pipe 23, which is provided with a sight glass 3D. The container 23 is provided with 20 a vent 3i and a gauge glass 32, and is normally lled with a quantity of oil 33, Connected with the bottom of container 23 is a pipe 34 which connects the suction end of a pump 35 which v may be of any suitable type. The pump 35 may 25 be driven by any suitable motor power such as electric motor 35. The pump 35 discharges through pipe 31 which leads into cylinder I above the level of piston I2 thereof. In line 31 is interposed a pressure adjusting device 38 ,30 which is provided with a valve 3;*3 normally closing a pipe 4B, communicating with container 28. A spring 4I tends to hold valve 39 on its seat` The tension on spring 4I may be adjusted by a nut 42. The container 28 is fitted with a drain v35 cock 43. The assembly just described may be mounted upon any suitable base 44 so that the apparatus may be transported as a unit,

In operation, nuts 3 are loosened and the cover 2 of container I is removed together with the 4L() screw threaded shaft 5 and the piston 1. The container l is then filled with heavy grease and the cover, together with the shaft and pist/on*L replaced and nuts 3 set tight. Crank 6 is tlfenfrotated to move the piston 1 downwardly, .forcing 45 grease 45 through pipe 9 past check valve II, into cylinder l0. The valve 21 is open during this operation. The piston I2 is provided with a projection 41 which limits the upward movement of the piston. When the piston I2 has 5o reached its upper limit of movement and the cylinder I0 is filled with grease, as will be apparent by the metallic sound occasioned by member 41 striking the upper wall of the cylinder I0, or by the resistance to further movement on crank 6, the motor 36 is started and oil is pumped from container 28 through line 34, through pump 35, through line 31, to the space Within cylinder ID above the piston I2. The valve 2i being open, the space above the piston I2 will fill with oil which will overow and pass through line 29 back into the container 28. Entrapped air and/or gases will be displaced by the oil and vented from the system through vent 3l. When the space within cylinder lil above the piston` i2 is lled with oil, which will be evidenced by the passage of oil through sight glass 30, the pump is stopped and valve 2 is closed. Gauge glass 32 is provided with calibration marks 45'. After the valve 2l is closed, if the level of oil within container 28 is below the uppermost of the calibration marks, vent 3l is removed and suiicient oil is added to bring the level of the 'oil within the container to the uppermost mark. Ii the oil level within the container is above the uppermost mark, an amount of oil is drained from container 2B through drain cock 43. When it is desired to dispense grease into the bearings of a device to be greased, as for example, a motor car, the pump is started. Oil discharged from pump 35 through line 3l to the top oi piston i2 will tend to force the piston downwardly, The check valve il prevents grease 'from backing through pipe 9. The grease dispensing nozzles being closed, grease cannot escape through the manifold I to the grease dispensing hose, The pressure will then build up. The amount of pressure necessary to move the grease with desired rapidity Varies with diierent types of greases, heavier grease requiring more pressure. The capacity oi the motor and pump unit is suficiently great to move the heaviest grease at a high rate of flow. If, for example, it was desired to move a heavy grease at a pressure of 5,000 pounds per square inch, the nut i2 would be adjusted to increase the tension upon spring dl until a pressure of 5,000 pounds showed upon gauge de. When this pressure is reached, valve 39 will be forced oi of its seat ley-passing the oil through pipe di) back into container 28. It will be observed that, no grease being dispensed, the oil is simply circulated from the container and back again, thus making no change oi the level of the oil within container 23. When nozzle 25 is operated to open the same, grease will pass therefrom at a predetermined pressure, due to the downward movement of piston `l2. The downward movement of piston l2 will increase the space within cylinder it above the piston,` which v will be filled with oil removed from container 28. It is apparent that the amount of grease dispensed will be faithfully reiiected b-y a decrease in the level of the oil in the container 28. When all of the oil in container 28 up tothe level as determined by the position of pipe 34 within the container 28 has been transferred from the container to cylinder ii), the piston I2k will be at the desired point of the bottom of its stroke, and

suction will be lost. This will be reflected by a drop of pressure in the gauge 46. At this time, valve 21 is opened and crank S is again operated as described hereinbefore.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other featuresA and sub-combinations. This is contemplated by and is within the scope of my claims. It is further obvious that various changes may be made in details within the scope of my claims without departing from the spirit of my invention. It is,

therefore, to be understood that my invention is not to be limited to the specic details shown and described.

For example, valve 3S may be replaced by a diaphragm or plunger, the movement of which is adapted to operate an electric switch or relay to cut oiT the electrical supply to the motor. In this arrangement, the motor will stop when the predetermined pressure is reached. Similarly, if an air motor is employed, the valve 39 may be made to operate to shut 01T the air supply to the air motor. If desired, in the case of an air motor, the control arrangement may be dispensed with and the air motor may be permitted to stall when the desired pressure is reached, This will depend upon the pressure of air supplied to run the air motor.

Having thus described my invention, what IY claim is:

i. A grease dispensing apparatus including in combination a cylinder, a piston within said cylinder, saidv cylinder being adapted to position grease on one side of said piston, a grease dispensing nozzle, means providing direct communication between the grease within said cylinder and said nozzle, a reservoir, liquid within said reservoir,y a pump adapted to draw liquid from said reservoir, a discharge conduit for said pump communicating with said cylinder on the other side of said piston, means for operating said pump to apply liquid pressure uponV said piston to displace the same to force grease out of said cylinder, a reliefvalve for said cylinder communicating therewith above said piston, said relief valve being adapted to lift at a predetermined pressure, means providing communication between the outlet o5 said relief valve and said reservoir, and a liquid level gauge for said reservoir adapted to show the liquid level therein, said gauge being provided with calibration marks.

2. In a grease dispensing apparatus, a cylinder adapted to contain grease, a piston in said cylinder, an oil reservoir, a pump for pumping oil from said reservoir into said cylinder behind said piston whereby oil is adapted to displace grease contained within said cylinder in front of Said piston, and an on level gaugevfor said reservoir showing the level of oil thereinsaidj gauge being provided with calibrationY marks.

WAYNE H. MCGLADE. 

